Cover means for vegetables and other plants



J. F. STEVENSON COVER MEANS FOR VEGETABLES AND OTHER PLANTS Filed Oct. 27, 1943 June 7, 1949.

8 Sheets-Sheet 1 \NVENTOQ,

o s n e V v S n. o S u n F n h o J J. F. STEVENSON COVER MEANS FOR VEGETABLES AND OTHER. PLANTS Filed Oct. 27, 1943 June 7,1949.

8 Sheets-Sheet 2 (NV ENTUK. John Ferguson 3+evensorx June 7, 1949. J.- F STEVENSON COVER MEANS FOR VEGETABLES AND OTHER PLANTS 8 Sheets-Sheet s filed Oct. 27, 1943 1 N V E N To 2, JohnFQYsUSQR June 7, 1949. J. F. STEVENSON 2,472,630

' 7 COVER MEANS FOR VEGETABLES AND OTHER PLANTS Filed Oct. 27, 1945 v 8 Sheets-Sheet 4 June 7, 1949. J. F. STEVENSON 2,472,630

COVER MEANS FOR VEGETABLES AND OTHER PLANTS Filed Oct. 2'7, 1943 1 8 Sheets-Sheet 5 Fig.5. I E I I 1 H1151:

\NVE NTofib 5 J hn Fe r3 0.50m Swevenson June 7, 1949. 'J F; STEVENSON 2,472,630

COVER MEANS FOR VEGETABLES AND OTHER PLANTS Filed Oct. 27, 1945 8 Sheets-Sheet 6 u Shvenson m June 7, 1949. J. F. STEVENSON COVER MEANS Fox VEGETABLES AND OTHER PLANTS Filed Oct. 27,1943

8 Sheets-Sheet 7 \NvEiN-rom J'ohn Fevsusoh $+evenson June 7, 1949. J. STEVENSON 2,472,630

' COVER MEANS FOR VEGETABLES AND OTHER PLANTS Filed Oct. 27, 1945 a Sheets-Sheet a E ii \N vs N'l'b r1 Sch Ferguson Sievenson PH-TN cover or frame members and means at interadjacent edges of the members soas to intermeshor cross each other whenthe sides-are set together and bearing surfaces on or parts of the members bridgelike structure, "said means'being adapted" Patented June 7, 1949 UNITED STATES fSP-ATTENT .QfFiFilCE COVER IVEANS FOR YEGETABLES AND OTHER PLAN'IIS John Ferguson Stevenson, Belfast, Northern Ireland Application October 27 In Great Britain 19 Claims. 1 This invention relates to cover means-such as cloches, frames,-glasshouses and the like which are used to protect vegetables or other plants.

One object of the invention is to provide cover means for plants comprising a plurality of cover or frame members having means at interconnectable-edges thereof whereby the members can be separably attached edge to edge to form a bridge-like, roof-like or equivalent covering struc-. ture, said means being adapted to lock the mem- "bers against, or adapted to limit, relative angular movement in either or both directions.

A furtherobject of the invention is to provide cover means for plants comprising a plurality of connectable edges thereof whereby the members can be separably attached edge to edge to form a bridge-like or roof-like covering structure, said means comprising projections spaced along the adapted to be engaged by the corresponding proj-ection or projections on the other member to prevent further relative angular or flatteningmovement of the members beyond a predetermined angle of preferably substantially less than 180.

A further object is to provide cover means in which each frame member comprises a longitu-- din-a1 member at the interconnected edge and the opposite edge and transverse members running between said longitudinal members characterised in that some or all of said transverse members are extended to form said projections. A further object of the invention is to provide cover means which comprise two or more cover or frame members each of the two or of the two provide headroom for the plants throughout the area of the two members. =A furtherobject of the invention is to provide" I for a glasshouse a covering structure which comprises a plurality of single bridgelike structures and means for detachably clamping the structures together to form a composite, continuous and rig id'bridgelike structure, each single bridge I like structurecomprising a plurality of frame or cover members having means at interconnectabl edges thereof whereby the members can be separably attached edge to edge to' form a single November '18, 1942 Vii '15 views of four further *to lock the members against relative angular --movement in either or both directions.

In order that the-invention may be clearly understoodit-wi11-nowbe described, but merely byway of example-with reference to theaccompan-ying drawings inewhich:

Figs. 1, 2, and 3-arerespectively. end, plan and side views of a pair-of frame members forming a covering structurein accordance with the invention.

Fig. =4-is a cross-sectional view to a larger scale on the line IV- 1V of :Fig. a2and Fig. 5 is a corresponding plan view.

"Figspoand =7 are "respectively end and plan frame members forming. a "covering structure in accordance with the invention.

Fig. 8 is-across sect on the'line VIII-VIII o a perspective views corresponding to Fig. 8 and showing an end of an upper transverse member and associated parts'with the associated glass pane removed for clearness.

'Figs. 9-and were respectively planand side 5-v iewsto a larger scale of l-a frame member as in Figs o and and-Fig. 9A is a detail view ofa transverse member.

Fig. 11 is a cross-sectional detail of an alternative rorm of interlocking projections and Fig. 12

is a corresponding planview.

Fig. l3 isa broken plan view of a further form -of frame member forming a covering structure in accordance with the invention and Fig. 14. is a corresponding end-view.

5'- .Fig. 'l-B'isa broken plan view of cover members forming a covering structure in accordance with the inventionandFig. 16 is a corresponding sec- 'tional view on the.line:'XVI-XVI of Fig. 15.

' liigsrlland 18 -arerespectively sectional and ionalv-iew to a larger scale f Fig. 7; and Fig 8A is ire-plan views of interlocking projection means alternativeto that in :Figs. 15 and16.

Figs. 19 .andrzo 'aresimilar views of further interlocking projection means alternative to that in Figs. 15 -and'l6.

Fig. 121 isanend view partly insection of a completeglass housefo'rmed of frame members in accordance with the inventionand Fig. 22' isa corresponding side :view.

iii'g. 23-is asectional. view toa larger scale of "the*interlockingprojection means in Figs. 21 and 22 and Fig. 24 lsa-correspond'ing plan view.

Figs. 25,26 and-'27 are respectively plan, side; and-endviews -of"-a"-fr'a-me-as used in Figs. 21 "and-22.- Figx28is "a detail view and'Fig. -29 is an elevacollapse or flattening movement. plained later this angle may be altered but not to tion of a further modification while Figs. and 31 are corresponding plan views, Fig. 32 is a diagrammatic view of the interlocking projections and bearings.

Referring to Figs. 1 to 5, the roof components of the covering structure consist of two identical frames each consisting of two wooden longitudinals l formed by four transverse wooden members 2 attached by nails or otherwise on top of the longitudinals. The glass panes 3 have their transverse edges supported in grooves i (Figs. 4 and 5) in the members 2 and their inner longitudinal edge supported in the grooved spacers 5 while their lower longitudinal edges are supported on the spacers 6. The grooves in the members 2 extend to the outer ends thereof so that the panes can be slid into and out of position. In Fig. 4 lower portions of the panes 3 are shown broken off to reveal the grooves 4.

The wall components'are constituted by downward extension means such as a skirt provided at the outer longitudinal edge of each frame at an angle of substantially more than 90 and consisting of a board 7 extending from one end to the other and at each end thereof soil-engaging legs 8 are attached, being attached in recesses in the longitudinals I and members 2.

The frames are detachably attached or interlocked at an angle of about 150 at their inner longitudinal edges and this is effected by extending each member 2 in the form of a half width projection 9 and forming an inclined bearing surface In on the end of the other half of the member 2 at the base of the projection. The projections 9 are strengthened by bars II and the abutting faces of the members I are suitably inclined so as to abut flat against each other.

It will be seen that the projection 9 of one member 2 engages scissorwise with the projection of the corresponding member 2 and at the maximum or limit angle as shown in Figs. 2 and 4 rests flat on or substantially flat on the bearing surface ID of the corresponding member 2. The angle between the projections, in the example 150, is sufficient to ensure that the frames are frictionally locked under their own weight at evenly spaced points along their length against As will be exless than a minimum angle below which the frictional lock would not be obtained. Such angle is hereinafter referred to as the limit angle. In addition to being locked by the projections 9 and bearing surfaces ID against relative angular movement the members 2 are in effect locked or gripped together against slipping apart by the engagement of the projections and bearing surfaces. The skirt is of a suitable height to provide head room for plants right to the outer edges of the frames and the legs 8 serve to engage the soil and maintain the frames from slipping when they are set at less than full width or angle. They may also serve to keep the skirt slightly clear of the ground for ventilation. A suitable size for the frame members, which is given merely by way of example, is four feet longitudinally and two feet transversely.

To form a continuous cloche any desired number of cover structures, as shown in Figs. 1 and 3, are set endwise in a row and the ends of the row may be closed in any suitable manner. For waterin purposes the skirt 1 of one frame may be raised and owing to the interlocking of the projections 9 and surfaces ID when at a frictionally locking angle to each other both frames can be conveniently tilted in this way about the opposite skirt to allow convenient access. Ventilation may be provided for by leaving a space between the adjacent ends of adjoining structures.

With the frames described and shown the width in relation to the height can be substantially greater than with the existing wire frame V or barn cloches so that a greater proportion of ground can be covered with less glass than hitherto. Moreover the frames are easily separable, easy to move and can be safely stored.

Referring to Figs. 6 to 10, the coverin structure consists again of two roof components and two Wall components, but in this construction the components are four identical frames. Each frame consists of two wooden longitudinals 12 having inclined abutting surfaces l3 and joined by four upper transverse members M having half width projections l5 and inclined bearing surfaces I6 at each end whereby the frames can be detachably interlocked at the limit angle as already described with reference to Figs. 1 to 5. The glass panes H are slid into grooves IS in the members I 4 and the longitudinal ends are supported on spacers 19. If two only of the frame members were inter-attached (as indicated in Fig. 6 where the line X-X denotes the ground surface) in the absence of a wall component at each side (such as a skirt and projections as in Fig. 1) each frame would make an unduly acute angle with the ground and there would be inadequate headroom near the sides of the frames. By using three frames or four frames in accordance with the present invention, the lines Y--Y and Z-Z respectively denoting the ground surface, adequate headroom throughout the area covered by the roof component or components is obtained. In the case of three or more frame members when the members assume the limit angle to each other they are automatically interlocked by their own weight to form a rigid structure provided the limit angle and the number of frames is such that the frames engaging the ground are substantially sloped inwards from their lower edges. In the example shown the limit angle is about but this may be altered to any suitable angle less than by altering the slope of the bearing surfaces 15. In these three or more frame structures the two outer frames constitute the wall components and are equivalent to the skirts in Figs. 1 to 5 in that they support the roof component or components (formed by the intermediate frame or frames) so as to provide adequate headroom across the full width of the roof.

As in the preceding example a plurality of covering structures as shown in Figs. 6 and 7 may be set end to end to provide a continuous cloche or elongated covering structure. In a typical example the frames are about 4' by 2' which in the four frame structures shown gives a height of about 3 and a base width of about 5', but it will be understood that the size of the frames may be varied.

As the frames are identical they are interchangeable and easy to manufacture and they can be readily moved and stored. Further, owing to the projections l5 and bearing surfaces It at one end of each transverse member I A being at opposite sides from those at the other end, it is possible to attach either edge of one frame to either edge of another frame. Thus, for instance, if the projections at one edge are damaged the frame can still be used provided that edge is put to the ground.

Figs. 11 and 12 show a modified form of interrocking projectionflthazt-"can be thew- 'rangement'as showr'i FigsafiamdWand in Figs. I t 3'; 'Theconstructioh of the frame members is the same'as: Figs. c to re except that each transverse memben'ii hasat cneendI-at central projection 2'0 of reduced acorrespohdine' slot or recesszit at thehtherendbetween two prog'ections zi. 1 The "slot has aiminclined bearing surface N adaptedWto-be engaged by the projection-"'20 anion. each sideofi the: projection 28- the transverse has. inclined bearing surfaces 26" adapted-"t6 be engaged-by the projections 25. The interl'ocking'acti'onf is the same as in Figih except thatthe' engagemerit of the projection 2U between the proj'ecti'oris positively-prevents relative endwise movement between thefraxnes. It will'he under stood that alF or the interroemng projections in Figs. 1 to re may he as in Fi gsi n and"12' and that the arrangement shown 'm Figs. I1 and i2 -is also suitable for frames 'havin gheavier endtran's verse members in whichcase, theintermedlate transverse members; if'anmfneeii not have interlocking projections-a In Figs. 13 and-1 4% the identical frarnemem bers-each consist of" two wooden l'o'ngitudinal's 21 joinedin this-case by" five" transverse wooden members 18" adapted tc receive four panes 29 which are sli'dfiritc "slots" 31 the members 28 and supported at their longitiidihal edges on the spacers 3|. The members Ware'eXtended at alternate ends to forr'rr fixll'fwi'dth projections 32' while the {other--end's ai echamferedor. inclinedto form the beairiii: Surfaces-"33 forthe projections- 32 of the corresbtihdi hg members: 28 of the adjacent? frames; It wilr'beunderstood that theprojec'tibns 3'2 and bearing surfaces 33 of any two pairs of adjacent transverse memhers 28 of two attached fi ai-nes ibrman interlock which operates as previously described and that the constructionis -sim blified thatthe members 28 are nQt'rediIced hr itrld tlfi"to form the projections; It is usually-"necessary?however; to use" 'lengitudinals" "for I the *althflttifig edges which are i more rigid than those necessaryfor-"the preceding examplesso asto resist the hend'i ng stresses 'set up in tIie Ibngiti-IdineIsMi-Ie to the interlocking action. It alsohe ilnder's'tood that 'to give a self-siipriorting" striitiire'ftheremiust at least: be three *p'aii s'-- of engaging brojections 32 and bearing surfaces 3%; that the frain'emembers; where the-projections"are ferrned by extensions. of" the transverse mer'nhers 28, have'to coirsi'st of at least"twc"paries'--with at least three transverse members. The structures as shown'in Figs. 1'3 and l lniay'heforrnedhntocontinuous cloches QreIoIIgated covering structures as previously described and threeor more 'frarnes' may be used as shownin Figs. 6 and T to form the covering structure: 7

In Figs. '15 and I6" eachicoverfmemberconsists of a. sheet of glass or other suitable=-m-aterial fi l-having at each oftwo'oppjosediedges twomembersv 35 of wood'or othersuita16le material which have slots 38 whereby gri'p' the sheet... Each" mei'fibe'r 35" has, a half width projection :iGl andiincli ned'hearing surface 3t! so that. they cen .5e.,a"etanat1y interlocked as previously described. with reference-t0 the preceding-examples. In. Figs. 1'7I and18 amodi'fleatidn of theatr rangeme'ntin Figs ilfiand T6 is shown; Here the "members" 39 and 40" arebf'metal or the like hue a slot "43 the proieetimrfli J-of the meme her 39. The engagemenv'oi; theiprojectionrfl with: the upper" andlower heating? surface or edge oi tl reslot interlocks-thei"slieets,-' at the angle this-case the hear-'- ing surface is of much smallerarew.

Figs; 19' and-2(9- sl'iow arrangement to the preceding one. except that the 'loclsingris enacted by the projections $5" and the spacedpros jectionsx it respectively engaeinw the hearing edges or surfaces. 411i and: the hearingiedg'es'vor surfaces- 481 The-lockingefiedt isr similar to that Figs. 11 andrlz butt'the beazingrsurfaces are or much smaller areaifi The structure's' shc wn'im Ffgsiqifssto ZO'RTEES- pecially suitable for iormhi'grcontinucus garden cloc'hes Or smalier eovering'istructures', and each structure may be formed of. two,i-t'hree or. more covermein'ber's. v I Figs. 21 and '22 show'a lar'ger structure': namely a glasshouse constructed from frame members such as Dutch lightsm'odifle i in accordance with the invention"asshdwnin Eigst'fiii and f2'7. Each light consists-"as usuar'er the two'l'ongiitudinals 49 and twctransterree larg'er) members 5B, the 'gl a's's 'panes" "51 heink': siipponted on the longitudinals se ene-rm hooves-5'2 in: the members 50', H

The ends of theitcerltliiers "51Fare extended to form half width 'prcjeetions fiiat the foot of which inclinedheaifihgsurfaces' 54- aire forrne'd on the ends of the n ienjihers. The longitudinals 49- haveinclined nieeti'ng facesii ahd frbm Figs. 2:3 and 24' it will he s en that-emy'two lightscan he det'acl'i'acb1y interlbc'ked "with je proiections 53 and surfaces engagirres issorwise'as previous 1y described; It wil 'al'sdhe'ncted tliat' the longitudinals '49 provide bearing-'surface-W- "(see especiallyFig. 25)"'wh'ichi engag'es the correspbn'd ingjaroj'ection 53 of t "-attache'd light'and'prevents relative end'wfse'movement'hetween the Each four frames form" a-' rigfd arched structure as already descfibed with re erencew Figs. 6 and '7' and a plurelitif of these are set closely end to end, the proii ection's 53 heifigisuppcrted on bricks 51" having: central rldges liil. Any um;- ber of such structures rn'ay'hje se -positioned and thecomposite-structureis closed at the ends by glazed Walls" surrounscty naming boards BII having internal "battens v forming" a frame which fits into-the-frame tinned 'bythe end members 56 of eachf e' d- 'arc' l:1e' "structure: The end walls andthfeiarchedistriictures are firmly clamped together hytie wires or; the like 62' ex;- tending inside close ftq theii'ghts anufl attached at their endsto hooks or screwed rods 63 extending. through the hattensB-l" and boards 60 an threaded platesififla andengagedby'thi mb screws or the like 64 whereby thenecessary; clamping pressure maybe agplie The lower side edges of the structure may against whichie'arthina b may beotherWiSe dispo's nd the nurnher there:- of maybe varied; 'Ihereineyhethreedisposed along each of the apices'between-the four lights or they may be disposed '{outside'ithe lights or they maybe di'spcsec linislde in suitahle 'pesitions to. serve for the training oftomato" or other plants. I

To exclude moistureflead or'the like strips 66 are'p'rovided albngthe afliceswherethe-iongitu dinals ie-abut.

- ,Dutch lights Jna'yj rags-e m boards: at

five arched structures will be about 15' long and about 6 high at the centre. It will thus be seen that the invention provides a commodious glasshouse that .can be readily assembled and taken down and which is built largely of identical frame members.

Projection and recess means may be provided on the abutting edges of adjacent arched structures, the said means being held in engagement by the effect of the clamping means and so keeping the arched structures in longitudinal alignment. As shown in Fig. 28 said projection and recess means may consist, for example, of dead end holes 66 in the abutting edges of the side members 50 of the frame members and removable .dowel pins 61 adapted to be engaged in said holes 50 as to keep the arched structures in longitudinal alignment.

The frame members shown in all of the drawings are of wood but it will be understood that any other suitable material may be used, for example, plastic or metal.

Instead of glass opaque panes may be provided in any of the examples shown where the cover means is to be used for forcing. In this case the .cover members may simply consist of sheets of opaque material, for example of asbestos or plastic having the interlocking projections formed thereon as shown in Figs. 29 to 31. The edges 69 of the sheets may be inclined to abut flush and have notches 10 to receive the projections of the adjacent sheet, these notches consisting of the inclined bearing surface H, shoulder 12 and side of the projection. It will be understood that these projections will prevent relative endwise movement of the sheets.

Where the cover means are simply to protect plants against birds the glass may be replaced by netting. It is to be understood that the term "bearing as used in the following claims covers not only fiat surfaces of substantial area as shown for example, in Figs. 4 and 5 and Figs. 8 and 8A but smaller surfaces or areas such, for example, as edges in Figs. 17 to 19. So far as the frictional interlocking effect is concerned the effective area of the bearing is not critical. The essential purpose of the bearing is to form a fulcrum for the correspondin projection. Referring, for example, to Fig. 32 which is diagrammatic, if

the right hand frame tends to slip outwards at 3 its outer edge along the ground its top end will tend to fall about a cm'ved path. That is to say, the right hand frame tends to execute a movement including a counterclockwise angular movement about the top edge F of the bearing surface Sof the left hand frame, but this angular movement is resisted by the bearing surface S (or the top edge F thereof) on the right hand frame engaging or pressing against the corresponding projection of the left hand frame. Similarly the left hand frame will tend to execute a clockwise angular movement about the top edge F of.the other frame's bearing surface S but this tendency will also be opposed by the engagement of surface S and the projection on the right hand frame. Thus the two tendencies to rotate about the spaced potential pivots F and F oppose each other and cause the projections and bearings to grip frictionally together under the effect of the weight of the frames. Thus it will be understood that the area of the bearings serving as .opposed fulcrums is not critical but in some cases it might be desired to have a substantial area as in Fig. 5 or 8.

For instance in the case of wood which might use for bearings the flat inclined surfaces 10 or I6 as in Fig. 5 or 8. Probably the pressure is concentrated more or less towards the potential pivots represented by the top edges F and F but it is found that such surfaces or top edges formed at the angle shown amply resist crushing and consequent further spreading or flattening of the frame beyond the angle for which they are made to be set, which spreading would be a substantial disadvantage in the formation of the continuous cloches as the several units might adopt different angles.

In other cases, for instance, where metal is used (as in Figs. 1'7 and 18) it may be desirable to have a smaller area of an edge giving a biting eifect due to the concentration of pressure.

The limit angle between the projections appears to depend inter alia on the angle of pressure and the friction between the bearing surfaces and the projections at the fulcrums. With the interlock in Figs. 17 and 18 where the projection enters between the two bearing surfaces or edges an interlock may be obtained at smaller angles than in Fig. 1 or 6. In the cases of structures formed of three or more withdrawably attached frames the angular setting must also be chosen in the light of the necessity for the outer frames to slope upwards and inwards sufficiently to make the structure adequately resist side pressure and sidewards collapse.

With the arrangement as in Fig. 1 the skirts or other side supports of the outer edges of the frames give sumcient headroom throughout the width of thestructure and at the same time enable the choice of a frictional locking angle substantially greater than the limit angle.

What I claim is:

1. A cover means for plants comprising a plurality of cover or frame members having interconnectable edges and complementary interlocking means at said edges whereby the members can be separably attached edge to edge to form a rooflike covering structure, said means comprising projections spaced along the adjacent edges of the members so as to cross each other when the edges are set together and bearing means on each member adapted to be engaged by the corresponding projections on the other member to prevent further relative angular or flattening movement of the members beyond an obtuse angle, and an integral soil-engaging skirt set at an angle at the remote edge of each cover or frliame so as to maintain plant head room at said e 8e.

2. A substantially plane frame member for horticultural cover means comprising a longitudinal at one edge and a soil engaging skirt set ,bearing surface at "the foot of the extension .adapted to receive scissorwise the corresponding projection of the other frame and in which the outer edge of the longitudinal is chamfered to enroofand of which atjleastztwo spaced proj ections engaged atan obtuse each projection on one of. them enga ng :81 co.-

them, the bearings Lthe projections. irict-ional'l-y claim A, in which :the roof gage flatly wit'h the ohamfered edge of thelongitudinal oftheothersframerwhen two frames are A interlocked.

4. An arched- ;cover'. struetureion plants; comprising at sleastthree adjoining-v porta'ble commnents of: which at least one. component forms a 4 roof and of which two compo e ts -fo m s de sup- .ports or wallsghighenough to :provide head-room -for plants throughout thearea covered "by the adjoining components are adapted for "withdrawable inter-attachment by theprovisionalong adjacent. edges of and bearings whereby these two adjoining components can be withdrawably angle to one another. with or bearings onsthe other of being disposed to function as opposed :fulcruzrnsv for l the projections. and to .grip under the weight of these components against flattening .oithe angular relationship and againstslipping apart; so that the several components -by virtue pisaid pro.- dections'and bearingsconstitutc aese'lf supportoperating ibearinging structure when supported at thelower ed e oi thesupports or walls.

structure as claimed: in is constituted by .two .ada-pted for said 5. An arched cover adjoining cover. components withdrawableintereattachment at adjacent in.- -ner edges and inwhich the,

two. components "forming the side. supports or.:-wal1s are ,constitilted by downward extension means on the respective cover: components at the outer edges thereof.

6. -An arched cover structure. as :olaimed in claim 4, in which the roof is formed "by acover :component and inwhich the two components forming theside-supports or :wa-llsrare adapted :ior said withdrawable attachment at their upper edges with the outer edges of thelrooi, :thesohtuseness of the angles between the roof and-the side supports or-walls being such that the side supports or walls are sloped inwards from their "lower edges to prevent sidewards. collapse of the "structure.

7. An arched cover structure as olaimed in claim 4, in whichtheroof is termed byia plural.- ity of cover componentsi'adapted for said withdrawable inter attachment at..adjacent edges.

and in which the two components forming the side supports or walls are adapted -for said withsdrawable att,achment at their .upperedges with the outer edges of the roof, theobtuseness of the angles between the roof and the side supports members on at last onecomponentwhlch are exrformzs P iZ QBSv Q tended at both ends to adapt that compon nt. i rasaid" wi hdrawa l inter-attachment at Jo. thrsd es.

9. An. arched oo er,stru tur. .-za la med in claim 4, in which each withdrawably attached component comprises a longitudinal member at the attached edge and at the opposite or outer edge and transverse members running between said longitudinal members and being extended to form said projections and in which the projection surface ocated in: \sai he set and wor d-w memb r to the pro ec on 551ml? 4 1?) W dth 0i heitransvcrsezmeny vher andthe bearing-isformed byzassurfaoelocated ii -said member. at. the :base or the-pro ection, the pram 80131011. and .z'bearing :suriaoe being located so as to engage inscissors fashion with the hearing surface and :nroieot on of. the .gpr esponding transversegmember of the: adjoining :component to allow identical; comnonents to be deteohably a ta hed with their. ends or onddormlns t ansverse membersilush so th ta plura ity o arched cover structures cam beset-end tov end without s aces therebetween tozform a. oontinu us' losed structure.

10. An archodrover :struotoroas .c a med in claim 4. in zwhioh aohwwithdrawably at ached .eo ponent-oom risos .a'l n -itudi alrmombor at the attachedtedgeand at.;-the pnosi or. uter ed e nd transverse-hie. hers r nning b tween said .11on itudinaiim mho s. and atzleastsome or which-transverse ;memborsareextended at both I ends toiorm :saidiproieetionszand inrwhi h th p jecti n s Qnltlrart of the width .oitho tran verse member andt ,sbearing isvform d by a ember atz thebase of the p omoti n; the pro. ti h-o d boorine surrtacehein iloooted so; as to. enga e in scissors tash on wit the bearing :sur a an proje tion of the.. or e po dine:transy rsemember of..-the ad oining: oom o ont tosallowwidentioal loomsweets t headl ohab ot ao d with th ir ends. or endorming transverse: mbers .fliish so that a plura ity of bodroovo is ruot rosoan tout s aces th rohotwoen to fo aroont no us closed stru tu e, he projection being half or approximately hiliw-the wid h of th transtorsemombor and the p on \tion at one. end :bein a the op os to sid o he the ot e end ,so tha itherdge of a wi hdrawabl aat aohah o oinponent may be so attached with either edge. of

-r ri i s two homes eoos itui co ponen s ad ed ei r a h e a one .adiaoeot ed es by the nro- -vision alon sa d d s ofwsnaood ro ec i ns an hearin s wh reby-th trams .oan bo ithd owably en a d a anan-gle o such ob u en ssthatwith ea h t c io on on of them en ag n a cooper tin bearinso the othe o hemrthe boar.- ings will function as opposed {plorums for-the proje t ons vand gr p the: nroi oi ons iriotionallv smdorwtho: ei ht oi these-zoomronents a ainst fla tenin oi thean sular r lationsh prandagainst s p n ap t. so thatethe oomnononts by virtue of said p oject ons ad bear ngs; oonst ut a se1i-su powing-structure,each frame at its outer edge havingan integral downward :wallriorming r omp non orv k'itzadapted to provide head room t he outenedges; o;- the drama-whenat sai obtu e an 1.2,. 7 An .arohedeore istmcture implan s mprisin three or m re "iram zadanted :ior interettaehment with; edge in. proximity to edge to form a :series making :an arched structure when supported at the 1 outer edges; the: outer -,f:ra mes of the soriesziormgin swell .components adapted t support; the {int rmedia e itrame or-rrames, whi h ioon titute root-forming. icomponen s. :hi h enou h to" provide; the xirequireda l-headroom throughout the area of the roof, said frames having spaced along their adjoining edges projections and bearings whereby the frames can be withdrawably engaged edge to edge with the projections crossing or lntermeshing and each enotholi- -.1...A-.n :a s d tr e struoturo .i r s ants. ro mworooi io mins s withdrawab e intenll projection 'on one frame engaging the corresponding bearing on the adjoining frame, the bearings being disposed to form opposing fulcrums for the projections so that when said bearings are engaged by the corresponding projections the adjoining frames contain an angle of such obtuseness that the projections and bearings and thus the frames are frictionally gripped or locked together in resisting relative angular flattening movement of the frames under the effect of the weight thereof and of such obtuseness that the outer supported frames of the series slope inwards from the lower edges to prevent sideward collapse of the structure.

13. A frame for edge to edge attachment to form an arched cover structure for plants or the like and having projections and bearings spaced along opposed edges whereby the frame can be withdrawably engaged at its opposed edges with the edges of complementary frames and with its projections intermeshing or crossing the projections of the complementary frames and in engagement with the corresponding bearings thereof and it bearings engaged by the projections on the complementary frames, the projections and bearings of said frame being so disposed that when they are respectively in engagement with the bearings and projections of the complementary frames the angle contained by any two adjoining frames is of such obtuseness that the projections and bearing surfaces and thus the frames are frictionally gripped or locked together in resisting angular flattening movement of the frames under the effect of the weight of the frames.

14. A frame as claimed in claim 13, comprising longitudinal members and transverse members which are extended at their ends beyond the longitudinal members to form the projections.

15. A frame as claimed in claim 13, comprising longitudinal members and transverse members which are extended beyond the longitudinals to form projections at both ends of less width than the transverse members and the latter have inclined bearing surfaces at the foot of said projections, the projection and bearing surface at one end of a member being disposed at opposite sides to those at the other end so that either edge of a frame may be interlocked with either edge of another.

16. A frame as claimed in claim 13, comprising longitudinal members of which consecutive or alternate transverse members are extended beyond the longitudinals at opposite ends to form the projections and the other ends are chamfered to form the bearing surfaces.

17. Cover means for plants comprising a plurality of identical frames each comprising spaced longitudinals and spaced transverse members which are extended beyond the longitudinals to form projections at opposite edges of the frame of lesser width than the transverse members and which have bearing surfaces formed at the foot of the projections, the frames being Withdrawably engageable together at said edges so that the projections and bearing surfaces engage scissorwise with the ends of the frames flush or in the same plane and detachably lock the frames when supported at their remote edges l2 against collapse or flattening movement beyond an obtuse angle and against slipping apart so that the frames form a self-supporting bridgelike or roof-like structure capable of being engaged endwise with a similar structure without spaces between the structures, the part width extensions and bearing surfaces at opposite edges of the frame and the bearing surfaces being positioned to give a predetermined angle of substantially less than so that at least three frames can be detachably interlocked to form a self-supporting and locking bridge-like structure with the two ground-engaging frames sloped inwardly from their lower edge.

18. For a covering structure which comprises a plurality of endwise abutting rooflike structures forming a continuous structure, walls for closing the structure and clamping means detachably clamping the end walls and the rooflike structures together, the rooflike structures each comprising a plurality of sheet-receiving frames having interconnectable edges and complementary interlocking means at said edges whereby three or more frames can be separably attached edge to edge with two of them engaging the ground and sloped inwardly from their lower edges; a sheet-receiving frame consisting of two spaced longitudinals and two spaced transverse members, the latter being extended and shaped at the ends to form part-width projections and inclined bearing surfaces at the foot of the projections adapted to engage scissorwise with corresponding projections and bearing surfaces on a corresponding frame to de tachably interlock the two last-mentioned frames against flattening movement beyond an angle of less than 180.

19. A sheet-receiving frame as claimed in claim 18, in which the two spaced longitudinals have outer edges that are chamfered to engage flatly with corresponding outer edges of an adjacent similar frame when both frames are interlocked at said angle, and in which the longitudinals also have ends projecting beyond the bearing surfaces on the transverse members of the first-mentioned frame to constitute notches which receive the projections of said adjacent frame and prevent relative longitudinal movement between the frames.

JOHN FERGUSON STEVENSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,221,664 Boyer Apr. 3, 1917 1,738,363 Edwards Dec. 3, 1929 1,960,001 Davies May 22, 1934 2,122,005 Foley June 28, 1938 2,200,706 Slater May 14, 1940 2,264,290 Blain Dec. 2, 1941 FOREIGN PATENTS Number Country Date 545,034 Germany Feb. 29, 1932 18,427 Great Britain 1888 17,648 Great Britain 1914 

